Structural beam

ABSTRACT

A composite wood/metal beam includes a metal support element having a vertical web and horizontal flanges which project from the top and bottom of the web. A plurality of studs which fit entirely between the flanges are attached to the support element. A wood member having the same length and width as the beam is attached to the flange at the top and bottom of the beam. Preferably, some of the studs are attached to the support element in a manner which allows them to be slid along the length of the beam.

BACKGROUND AND SUMMARY OF THE INVENTION

[0001] This invention relates to a load supporting beam, and inparticular to such a beam which is composed of both wood and metalcomponents.

[0002] Beams used in residential and light commercial construction aregenerally made of wood. Lightweight beams are typically dimensionlumber. Intermediate beams are wood I-beams and glue-lam beams are usedfor heavy loads. However, wood is becoming less available and thus moreexpensive. Wood beams also have a relatively low strength to weightratio. In addition, glue-lam beams deteriorate with time and sag.Finally, when a wood beam fails due to overload conditions, such asextreme snow loads, it generally completely fails, which causes seriousdamage to the structure.

[0003] While metal I-beams could be used for residential and lightcommercial construction, they generally are not. Available metal I-beamsare larger and stronger than are required for this type of application.Thus, they are heavier and more expensive than they need to be. Metalbeams also typically require stiffening or bracing, which is laborintensive, and thus expensive. In addition, the majority of thestructure in this type of construction is wood and it is more difficultto attach wood components to metal components than it is to attach themto other wood components. Finally, finish work, such as installingSheetrock, cabinetry and trim is typically done by carpenters who aremore familiar with and comfortable with wood components than they arewith metal components.

[0004] The subject invention provides a composite wood and metal beamwhich is lighter and stronger than wood alone, does not sag with time,is less expensive than wood and has plentiful nailable surfaces. Thebeam has a metal support element having a vertical web with horizontalflanges at its top and bottom extremities. Wood studs, which fit betweenthe flanges and are contained entirely within them, are attached to thesupport element at desired locations along the beam. A wood member isattached to one or both of the flanges at the top and/or bottom of thebeam.

[0005] In one preferred embodiment the support element is a C-shapedchannel. In this embodiment, spacer blocks are attached to the channel,on the side opposite the side the studs are attached. The wood member isdimensioned to cover the flanges of the channel and the ends of thespacer blocks.

[0006] In another preferred embodiment, the support element isback-to-back C-shaped channels, the webs of which are joined together.In this embodiment the studs are located on both sides of the beam.

[0007] In another preferred embodiment, the support element is a singleI-beam. In this embodiment, studs also are located on both sides of thebeam.

[0008] Another aspect of the invention is that some of the studs can beslidably attached to the beam. This allows them to be located whereneeded once the beam is installed. One way to slidably attach the studsto the beam is to provide a downwardly facing lip at the extremity ofthe top flange and an upwardly facing lip at the extremity of the bottomflange so that the studs can fit between the web and the lips.

[0009] The foregoing and other objectives, features, and advantages ofthe invention will be more readily understood upon consideration of thefollowing detailed description of the invention, taken in conjunctionwith the accompanying drawings.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

[0010]FIG. 1 is an exploded view of a beam embodying the subjectinvention.

[0011]FIG. 2 is a perspective view of the beam of FIG. 1.

[0012]FIG. 3 is a perspective view of a modified version of the beam ofFIG. 1.

[0013]FIG. 4 is an exploded view of an alternative embodiment of thebeam of the subject invention.

[0014]FIG. 5 is an exploded view of yet another embodiment of the beamof the subject invention.

[0015]FIG. 6 is a perspective view of the beam of FIG. 5.

[0016]FIG. 7 is a perspective view of a modified version of the beam ofFIG. 5.

[0017]FIG. 8 is an exploded view of yet another embodiment of the beamof the subject invention.

[0018]FIG. 9 is an exploded view of a modified version of the beam ofFIG. 8.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

[0019] Referring now to the drawings, a beam 10 combines a metal supportelement 12 with a wood member 14. The resulting beam provides thesuperior strength to weight ratio and low degradation of a metal beam,with the ability to attach surrounding structure and surface materialsto the beam with nails, which makes it more desirable for residential orlight commercial construction. In addition, the combination of wood andsteel provides greater strength than either material would providealone.

[0020] Referring now to FIGS. 1 and 2, in a first embodiment of the beamthe metal support element is a C-shaped channel 16 having a vertical web18. Extending outwardly from the top extremity of the web is a topflange 20 and extending outwardly from the bottom extremity of the webis a bottom flange 22. In the embodiment illustrated, the top flange 20has a downwardly extending lip 24 at its extremity and the bottom flangehas an upwardly extending lip 24 at its extremity. Channels of this typeare common in the building arts and are typically rolled steel. The lips24 are not essential, but they do add some strength and they accommodateattachment of wood studs 26 to the beam.

[0021] The wood studs 26 have a thickness which is slightly less thanthe width of the flanges 20 and 22 and a height which is slightly lessthan the height of the web 18. Thus, they fill the space between the web16, the lips 24 and between the top and bottom flanges 20 and 22. Thestuds 26 typically are dimension lumber and thus have a width which isgreater than their thickness. The studs typically are glued to theflanges 18 by an epoxy adhesive. However, depending on the length of thebeam, one or more of the non-end studs may not be glued to the flange.As a result these studs can be slid along the beam to a desiredlocation. This provides flexibility in the use of the studs as a nailingstrip. In addition, it allows multiple studs to be placed at points ofload concentration on the beam.

[0022] Wood spacer blocks 28 are attached to the web 18 on the otherside of the beam 12. This also preferably is done with an epoxyadhesive. The spacer blocks typically have the same dimensions as thestuds 26 and one of their wider sides is placed against the web 18.Normally a stud and spacer block will be placed at each end of the beamand the number of internal studs and spacer blocks will depend on thelength of the beam. The studs and spacer blocks add strength to the beamand serve as nailing strips.

[0023] If desired, the studs and spacer blocks can be covered by thinC-shaped metal caps 30. The caps 30 are attached to the studs and spacerblocks with an epoxy adhesive. Because the studs and spacer blocks arerelatively thin they are prone to splitting when nails are driven intothem and the caps 30 greatly reduce the amount of splitting.

[0024] Finally, a wood member 14 is placed on the top and/or bottom ofthe beam to act as a nailing strip. The wood member has a width equal tothe combined width of the flange 20 or 22 and the thickness of thespacer block. The wood member is attached to the respective flange andthe ends of the spacer blocks by an epoxy adhesive. The embodimentillustrated in FIGS. 1 and 2 shows a wood member 14 attached to both thetop and bottom of the beam and the embodiment shown in FIG. 3 shows itattached to only one side of the beam. In the beam illustrated in FIGS.1 through 3 the studs 26, spacer blocks 28 and wood members 14 all are2×4 dimension lumber. If it is desired to make the beam larger and stillutilize the same size channel 16 the spacer blocks 28 can be placed withtheir narrower sides facing the web 18 and the wood member 32 be 2×6dimension lumber, as shown in FIG. 4. In this case the caps 30 are notrequired on the spacer blocks, since the spacer blocks are less likelyto split in this orientation.

[0025] The foregoing beam has sufficient strength for light applicationssuch as trusses and typically would used instead of dimension lumber orwood I-beams. For larger applications, which typically requireglue-lams, the beam of the subject invention would need to have athicker web. This can be accomplished using the same components byjoining together two of the C-shaped channels 16 with their websback-to-back as shown in FIGS. 5 and 6. In order to maximize thestrength of this beam, the two channels need to be strongly connected.This can be accomplished by spot welding.

[0026] With this embodiment studs 26 are used on both sides of the beamand they are covered with caps 30. Sliding studs can also be provided onboth sides of the beam if desired, but this would not always be thecase. If the channels 16 are the same size as the channels in theprevious embodiment a 2×4 wood member 14 would be used. While this beamhas the same width as the beam shown in FIG. 3, it is considerablystronger. Not only is the web twice as thick, a two-piece web isstronger than a single piece web having the same thickness. In addition,this beam has twice the flange area as the beam shown in FIG. 3. Thesame beam is shown in FIG. 7 with the wood members 14 only on one side.

[0027] If desired, the support element formed from two back-to-backC-shaped channels can be replaced by a single I-shaped channel 34, FIG.8. The channel 34 would have an integral web 36 and flanges 38 with theflanges extending from both sides of the web. Otherwise this beam issimilar to the beam shown in FIG. 6 and has studs 26 and caps 30 on bothsides. Typically this beam would not have lips on the flanges so itwould not have slidable studs. This same beam is shown in FIG. 9 withthe wood member 14 only on one side.

[0028] The terms and expressions which have been employed in theforegoing specification are used therein as terms of description and notof limitation, and there is no intention, in the use of such terms andexpressions, of excluding equivalents of the features shown anddescribed or portions thereof, it being recognized that the scope of theinvention is defined and limited only by the claims which follow.

1. A beam for use in supporting a structural load, said beam having apre-determined length, height and width, comprising: (a) a metal supportelement having a vertical web with a top end and a bottom end and a pairof horizontal flanges, said flanges being oriented normal to said web,one of said flanges being located at the top end of said web and theother of said flanges being located at the bottom end of said web, saidflanges extending outwardly from said web a predetermined distance; (b)a wood member having a length and width substantially equal to thelength and width of said beam, one of said wood members being attachedto at least one of said flanges; (c) a plurality of studs having aheight such that they will fit snugly between said flanges and athickness which is equal to said predetermined distance so that saidstuds are contained entirely between said flanges, and a width which isgreater than said thickness, said studs being attached to said supportelement.
 2. The beam of claim 1 wherein at least one of said studs is asliding stud which is attached to said support element in a manner suchthat it is slidable along the length of said beam.
 3. The beam of claim1, including C-shaped metal caps which are dimensioned to fit over saidstuds, one of said caps being attached to each of said studs.
 4. Thebeam of claim 1 wherein said support member is a C-shaped channel. 5.The beam of claim 4 wherein said flange at the top end of said web has adownwardly projecting lip at the distal extremity thereof, and saidflange at the bottom end of said web has an upwardly extending lip atthe distal extremity thereof.
 6. The beam of claim 2 wherein saidsupport member is a C-shaped channel.
 7. The beam of claim 6 whereinsaid flange at the top end of said web has a downwardly projecting lipat the distal extremity thereof, and said flange at the bottom end ofsaid web has an upwardly projecting lip at the distal extremity thereof.8. The beam of claim 7 wherein said lips are what attach said slidingstuds to said beam.
 9. The beam of claim 4, including a plurality ofspacer blocks which are substantially the same size as said studs, saidspacer blocks being attached to said web, on the side thereof which isopposite the side said studs are attached, with the wider side thereofbeing in contact with said web.
 10. The beam of claim 9, includingC-shaped metal caps which are dimensioned to fit over said spacerblocks, one of said caps being attached to each of said spacer blocks.11. The beam of claim 10 wherein said wood member has a width whichentirely covers said support element and said spacer blocks.
 12. Thebeam of claim 1, including a plurality of spacer blocks which aresubstantially the same size as said studs, said spacer blocks beingattached to said web, on the side thereof which is opposite to the sidesaid studs are attached, with the narrower side thereof being in contactwith said web.
 13. The beam of claim 2 wherein said support member istwo C-shaped channels having back to back webs which are joined to oneanother.
 14. The beam of claim 13 wherein said studs are located on bothsides of said support members.
 15. The beam of claim 14 wherein theflange at the top end of the web of each of said channels has adownwardly projecting lip at the distal extremity thereof, and theflange at the bottom end of the web of each of said channels has anupwardly extending lip.
 16. The beam of claim 15 wherein said lips arewhat attach said sliding studs to said beam.
 17. The beam of claim 13,including C-shaped metal caps which are dimensioned to fit over saidstuds, one of said caps being attached to each of said studs.
 18. Thebeam of claim 1 wherein said support member is an I-shaped channel. 19.The beam of claim 18 wherein said studs are located on each side of saidI-shaped channel.
 20. The beam of claim 19, including C-shaped metalcaps which are dimensioned to fit over said studs, one of said capsbeing attached to each of said studs.